User Guide

1 pulse per litre of flow
70 pulses per
litre of flow
Flowmeter with
K-factor of 70
÷
Flowmeter K factor factor
Set to 70
÷
Rate scale factor 5cale . r
Set to 4.5461
÷
Total scale factor 5cale . t
Set to 1000
x
Timbase t-ba5e
Set to 60 for rate per minute
Total Display
Cubic metres of flow m³
Rate Display
Gallons of flow per minute
1 pulse per
gallon of flow
1 pulse per cubic
metre of flow
Fig 10 5cale . r and t-ba5e set to provide a Rate Display
in Gallons / minute
4.4 Timebase: t-bA5E
As described in the previous section, the rate scale factor
5cale . rdenestheengineeringunitsoftheratedisplay.
TheRateTotalisercandisplayrateofowpersecond,per
minute or per hour.
The Rate Totaliser timebase t-ba5e enables the output
from 5cale . r to be multiplied by 1, 60 or 3,600 to produce
a rate display per second, per minute or per hour as shown
below:
t-ba5e menu
options
tb-1 x1forow/second
tb-60 x60forow/minute
tb-3600 x3600forow/hour
For this example the rate display is required in gallons per
minute, therefore t-ba5e is set to tb-60 as shown in Fig 6.
4.3 Rate scale factor 5cale . r
Function 5CALE . r is similar to 5cale t described in the
previous section. As shown in section 4.1 the Rate
Totaliser function factor is used to convert the number of
inputpulsesreceivedfromtheowmeterintoengineering
units such as litres or gallons.
If the Rate Totaliser’s rate display is required in the
engineering units produced by factor no further scaling
is required. However, to enable the rate display to be
in different engineering units, or in multiples of the
engineering units produced by factor, such as thousands
of litres or gallons, an additional scaling factor 5CALE . r is
included.
Functions 5cale . r and 5cale . t receive their inputs from
factor. Both are independently adjustable which enables
the Rate Totaliser to have rate and total displays with
different units of measurement.
5cale . r is a dividing factor adjustable between 0.0001
and99999thatenablesrateofowtobedisplayedinthe
required engineering units. It is used in conjunction with
the Rate Totalisers timebase t-ba5e which determines
whethertheowrateisdisplayedpersecond,perminute
or per hour.
Continuing the example shown in Fig 8 and assuming
thattheowratedisplayisrequiredingallonsperminute.
Fig 10 illustrates how 5cale . r is set to produce a rate
display in gallons. Each pulse output from the factor
functionrepresentonelitreoftotalow.Thereare4.5461
litres in an imperial gallon, therefore the output from factor
requires dividing by 4.5461 to convert it to imperial gallons.
This is achieved by setting 5cale . r to 4.5461.
4.3.1 Resolution
The output from factor will determine the resolution of
the Rate Totaliser.   If increments of ow smaller than
oneK-factorunitofmeasurementaresignicant,factor
should be reduced.
The effect of reducing factor for a owmeter having a
K-factor of 200 pulses per litre are shown below.
Factor Instrument resolution
200 1 litre
20 0.1 litre
2 0.01 litre
TOTAL
________
RATE
BA337E
6501
50 . 0
Total and Rate are displayed simultaneously and can
have different units of measurements
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